In my previous U.S. Pat. No. 4,730,797 entitled "Inflatable Core Orbital Construction Method and Space Station" filed Aug. 12, 1985, I disclosed an automated method and operating system for constructing large continuous-walled structures in orbit by robotics. In that method, a lightweight, non-elastic, inflatable surface with thin flexible walls is transported to orbit and inflated like a balloon to form a semi-rigid surface. The surface is then used as a guide for constructing the wall of the structure by wrapping the inflated surface with long sheets of flexible high-strength material until the desired wall thickness is obtained. The wrapping process is accomplished automatically by a wrapping machine.
Unfortunately, that method of orbital construction had a number of operational problems. For example, the diameter could not be very large because the inflation pressure would generate stress that could easily exceed the stress limitations of the inflated surface. Since the pressure had to be relatively low, it did not serve very well as a firm guide surface for the wrapping material and could be deformed during the wrapping process. The inflated surface was also subject to accidental deflation before it could be completely wrapped and made rigid. It was also limited to finite dimensions. But the most serious defect inherent in that method of orbital construction was the fact that the wrapping machine had to move around the inflated surface along a precise predetermined path while it wrapped the material around it. This was a technically difficult and tedious process since the machine had to move over the surface many times to build up the wall thickness by wrapping it with many layers of wrapping material. Consequently, the machine required considerable time to construct the structure and it required considerable monitoring to make sure it was moving along the required path.
Although the present system is also based on the use of wrapping material for wall building, it represents an entirely new system and operating method because it does not require any preinflated guide surface and does not require the machine to travel anywhere during the construction process.